In the recording at 12:26:21 in response to 'Request Level' I am almost certain that the pilot does not say as written in the transcript, 'Malaysian 370 we are ready requesting flight level...'
It sounds as though he is saying '770 we are ready...'
which makes no sense at all if that's correct. Though it is probably irrelevant.
Listen: Missing Jet MH370 Pilots Talking to Air Traffic Control - NBC News